Are long hours the secret to success? Here’s how to maximize your productivity to get ahead at work.

Superbowl-winning football coach Jon Gruden used to wake up every morning at 3:17 a.m. to the Notre Dame fight song. Even when that clock “expired of natural causes,” as he told the Bleacher Report, he continued to get up early: Now a sportscaster, Gruden is still at his desk most days by 4 a.m., and he stays there (save for a workout) for about 12 hours.

But Gruden’s alarm clock isn’t the only thing that expired. Although he was the youngest coach to win the NFL title back in 2003 at age 39, he got fired as coach of the Tampa Bay Buccaneers in 2009 after a losing streak.

So why does Gruden stick to his long hours, despite his career ups and downs? It’s a sign that he believes his coaching failures had little to do with working too much. And he has good reason to think that: As of 2015, he was reportedly the highest-paid on-air employee at ESPN.

But while many people swear by putting in long hours, the debate continues about just how much work it takes to be successful.

The average person may think that just showing up to their job and doing great work for eight hours a day is plenty. And Tim Ferriss, author of The 4-Hour Workweek, says you can get away with even less. “Life doesn’t have to be so damn hard,” he wrote. “Most people, my past self included, have spent too much time convincing themselves that life has to be hard, a resignation to 9-to-5 drudgery in exchange for (sometimes) relaxing weekend and the occasional keep-it-short-or-get-fired vacation.”

But we all know that many successful people burn both ends of the candle. For example, the 256 CEOs who responded to a 2015 survey by the business platform Domo reported working a mean of 58.15 hours per week, or between 10–11 hours per week day, “plus nearly six hours of extra time on the weekend,” Time reports. (They also get significantly less sleep, with those same CEOs average 6.7 hours a night, compared with 8.75 for regular workers.)

For some, even 11 hour work days aren’t enough. “There are 168 hours in a week. You should be working most of them,” self-made millionaire and New York Times best-selling author Grant Cardone told CNBC. And when you’re not working, you should be reading, Warren Buffett famously advised: “Read 500 pages like this every day. That’s how knowledge works. It builds up, like compound interest.”

So how hard should you be working to get ahead? We checked in with executives, academics and others who put in seemingly crazy hours to get the answers.

Is the Amazon way the right way?

While working long hours is fairly common in the tech industry, Amazon is famous for a particularly grueling workplace culture, which the New York Times described in 2015 like this: “At Amazon, workers are encouraged to tear apart one another’s ideas in meetings, toil long and late (emails arrive past midnight, followed by text messages asking why they were not answered), and held to standards that the company boasts are ‘unreasonably high.’”

While Amazon disputed parts of the article, it did not deny that some workers put in long hours. That strategy appears to be working: Amazon is now worth nearly half a trillion dollars, and the “Amazon effect” has been widely blamed for the rapid rate of retail store closings in the U.S. in recent years.

Likewise, Gary Vaynerchuk, host of the popular Apple show Planet of the Apps advises an approach to life that “cuts out leisure” in order to maximize focus on your objectives. “I push work ethic because it’s a variable, and I believe it’s far more controllable,” he said. “Hard work really matters.”

But he adds an important caveat: If you don’t have talent, he argues, it doesn’t matter how many hours you work a day. As he explains in the video below, success requires a “cross section of work and talent.”

Gary Vaynerchuk advocates for a life that “cuts out leisure” on The #AskGaryVee Show.AskGaryVee/YouTube

When burnout kills productivity

Long hours are also the norm in medicine, where 12-hour shifts have largely replaced the standard eight-hour work day for nurses and first year medical residents are now allowed to work up to 24 hours straight. The thinking is that reducing the number of shift changes per day will also reduce the chance of errors when one worker hands off care of patients to the next shift. But a large survey of 22,000 nurses by researchers at the University of Pennsylvania, published in Health Affairs in 2012, found that burnout among nurses and patient dissatisfaction increased when nurses worked 10 or more hours.

It’s not just medical professionals who suffer from working long hours. Hampton Catlin, senior director of engineering at Rent The Runway, told Mic in an email that managers at the fashion startup actively stop workers from putting in long hours “and producing shitty code.”

As he explained on Medium last year, “Engineers who are overworked come up with bad ideas, have low overall velocity, and often end up with overly complex and bug-laden code,” he wrote. “They will eventually burn out and will leave you with a lot of badly written code that no one on the team knows how to work with.”

Research backs Catlin’s claims. Stanford computer science professor Eric Roberts noted that productivity (measured as the amount of output produced per hour) “generally goes down as hours worked increases.” He added that when employees are made to work longer than 40 to 50 hours per week (or 8 to 10 hours per day), “their total output over an extended period of time will drop below the level it had been when only 40 to 50 hour workweeks were required.”

“In other words, in such cases, more work was actually shown to be detrimental to output,” Roberts wrote. The reason? At some point, stress and fatigue set in. And if employees are too overworked, output can become negative — meaning people start to make mistakes.

Why do Americans work so much?

Of course, some workers, like lawyers — or anyone who gets paid by the hour for that matter — are incentivized to work longer hours based on the nature of how they get paid. Lawyers at many large firms can often work up to 70 hours, the Atlantic reported. The American Bar Association does not have any firm rules on billing hours, instead only offering guidelines on communicating rates with clients, spokesperson Priscilla Totten said in an email.

As technology has automated more traditional work — from building cars to digging ditches — it might seem that people would work shorter hours as opposed to longer ones. Instead, we’re often working more: “The share of employed American men regularly working more than 48 hours per week is higher today than it was 25 years ago,” according to a landmark 2005 study by economists Peter Kuhn and Fernando Lozano.

The authors posited that many salaried men (as opposed to hourly workers) are being motivated by “marginal incentives” such as the possibility of earning a bonus, raise or promotion, or to “signal to the labor market that they are productive and ambitious and thus suitable for a better job in another firm.”

The trend toward working more hours has a class break down as well. While less educated men saw their leisure hours grow nearly three hours to 39.1 hours between 1985 and 2007, highly educated men saw their leisure hours fall more than one hour to 33.2 hours, a 2012 study found. The same trend was found for women, although it was less dramatic: Highly educated women saw their leisure time decrease by 1.9 hours to 30.3 hours while less educated women saw their leisure time grow by 0.2 hours to 35.2 total hours per week.

Highly educated workers may put in more hours because they have more options over how much they can work while those with less education and working for less pay may be doing shift work. “Most middle-class and poor Americans have very little control over their work schedules — and that’s assuming they can even find a job in the first place,” University of Southern California lecturer Anthony Orlando wrote in 2014.

Notably, the trends are different trends in Europe, where, “rich European countries work significantly less than Americans, and yet seven of the 10 happiest countries of the world are in Europe,” the Atlantic’s Derek Thompson wrote. “There is a workaholic mania among educated wealth-seeking American men, who seem uniquely devoted to working any number of hours to get rich,” he added.

Focus on results, not hours logged

At the end of the day, what matters most may not be how many hours you put in, but what you have to show for your efforts. As Susan Wojcicki, CEO of YouTube, told the Wall Street Journal, “I [keep] reminding people that success is not based on the number of hours that you’ve worked. It isn’t like venture capitalists say, ‘Well, how many hours are you planning on working?’ They ask, ‘What is your insight? What can you bring to the table?’” She also notes that if you’re working 24/7, you’re not going to be able to come up with interesting ideas.

That may involve being a pro at work-life balance, which is especially tough if you have kids. Lisa LaCasse, an executive with the American Cancer Society and mother of four kids, told Fortune that she manages a work-life balance by seamlessly blending the two. What helps? Getting to a point in your job where you’ve established enough trust with your managers that you can make trade-offs with them about when and how you can meet your targets.

“I’ve never asked permission for the flexibility of my job,” she said. “I think women in particular need to feel more empowered to do that. No one ever told me to do it, I just did.”

Working smarter, not harder

Productivity, rather than raw hours worked, seems to be the name of the game. Maybe you will need to put in more hours to finish a project on time. Or maybe you need to scale back in order to increase the quality of ideas and work you produce.

“Carrying your weight and surprising your manager with peak productivity is a surefire way to impress and prove you are a valuable asset to the company. If you feel your productivity slipping, take strides to step up your game and increase your daily and weekly output,” Business Insider notes.

For some that might mean figuring out what time of day you are most productive. Lauren Milligan, a career advancement coach, told Mic in an email that although she starts her work day at 4 a.m., “the amount of hours I put in doesn’t have a lot to do with the time I arise. Normally I put in about 8-10 hours.”

Need help boosting your productivity? There are now loads of productivity apps available. Mic’s Susmita Baral suggests Priority Matrix if you “suck at knowing what to do when” and are “guilty of procrastinating on a time-sensitive task for something with no deadline.” Here are 21 more productivity tips from leadership expert Robin Sharma.

Lastly, give yourself breaks. Tony Schwartz, the author of Be Excellent at Anything, argues that humans are not meant to run continuously at top speed, like computers. Quite the opposite. “Human beings are designed to be rhythmic,” he told the Harvard Business Review. “The heart pulses; muscles contract and relax. We’re at our best when we’re moving rhythmically between spending energy and renewing it. We need to recognize the insight of athletes, who manage their work-rest ratios. We encourage people to work intensely for 90 minutes and then take a break to recover.”